EDCA operation to improve VoIP performance in a dense network

Abstract

This disclosure relates to wireless communication techniques for high short packet density scenarios. According to some embodiments, a wireless device may determine whether a wireless medium is experiencing crowded short packet conditions during a first period of time. The wireless device may select an operational mode from at least a first operational mode and a second operational mode based at least in part on whether the wireless medium is experiencing crowded short packet conditions. The wireless device may perform wireless communication on the wireless medium according to the selected operational mode.

Description

PRIORITY CLAIM[0001]The present application claims benefit of priority to U.S. Provisional Application No. 61 / 952,291 titled “EDCA Operation to Improve VoIP Performance in a Dense Network” and filed on Mar. 13, 2014, and to U.S. Provisional Application No. 61 / 952,293 titled “Control Frame Format for EDCA Enhancement” and filed on Mar. 13, 2014, both of which are hereby incorporated by reference in their entirety as though fully and completely set forth herein.FIELD[0002]The present disclosure relates to wireless communication, including to techniques for modifying EDCA operation in dense IEEE 802.11 wireless systems.DESCRIPTION OF THE RELATED ART[0003]Wireless communication systems are rapidly growing in usage. Additionally, there exist numerous different wireless communication technologies and standards. Some examples of wireless communication standards include GSM, UMTS (associated with, for example, WCDMA or TD-SCDMA air interfaces), LTE, LTE Advanced (LTE-A), HSPA, 3GPP2 CDMA200...

AI Technical Summary

Benefits of technology

[0010]As one possible such operational feature, use of request-to-send (RTS) and clear-to-send (CTS) indications may be enabled for non-voice packets in a Wi-Fi network. Since RTS / CTS indications may be relatively short, the consequences of a collision between such packets and other short packets may be relatively small; for example, such a collision may result in the wireless medium being unavailable for a relatively short amount of time relative to a collision between a short packet and a long packet, in which case the wireless medium may be unavailable for the entire length of time during which the long packet is being transmitted. If the RTS / CTS is successful, the chance of a collision between the long packet and another packet may be greatly reduced.

[0011]As another possible such operational feature, a certain number of slots after each Distributed Coordination Function (DCF) Interframe Space (DIFS) may be reserved for voice packets. For example, if a wireless device has a non-voice packet to be transmitted, and the backoff counter is below the reserved number of slots after a DIFS, the backoff counter may be increased (added to) to a number which is equal to or higher than the reserved number of slots. In this way, it may be ensured that only voice packets will be transmitted for the reserved number of slots. By the time the backoff counter for a non-voice packet reaches zero, the likelihood of the packet being transmitted without a collision may be greater than without such a feature.

[0012]If desired, any or all such features (among other possible features) may be used in combination. Such a combination may further decrease the likelihood of collisions between long and short packets, and may (at least in some instances) substantially increase overall network throughput in crowded short packet conditions.

[0013]Utilizing different operational modes and / or different operational features depending on the short packet state of the wireless medium may improve overall network efficiency, at least in some instances. For example, in the case of Wi-Fi, using EDCA for both uplink and downlink communications may provide excellent overall performance in uncrowded short packet conditions, but performance may degrade as the number of short packets in the network increases, while using EDCA for downlink communications and legacy DCA for uplink communications may provide better overall performance in crowded short packet conditions, but may not match the performance achieved by using EDCA for both uplink and downlink communications in uncrowded short packet conditions.

Problems solved by technology

For example, a wireless communication technology which provides good performance with a smaller density of devices with a certain configuration might exhibit degraded performance with a larger density of devices with the same configuration.

For example, if the wireless medium is experiencing crowded short packet conditions, there may be a greater chance of collisions occurring between short and long packets than under uncrowded short packet conditions.

Since RTS / CTS indications may be relatively short, the consequences of a collision between such packets and other short packets may be relatively small; for example, such a collision may result in the wireless medium being unavailable for a relatively short amount of time relative to a collision between a short packet and a long packet, in which case the wireless medium may be unavailable for the entire length of time during which the long packet is being transmitted.

Such a combination may further decrease the likelihood of collisions between long and short packets, and may (at least in some instances) substantially increase overall network throughput in crowded short packet conditions.

For example, in the case of Wi-Fi, using EDCA for both uplink and downlink communications may provide excellent overall performance in uncrowded short packet conditions, but performance may degrade as the number of short packets in the network increases, while using EDCA for downlink communications and legacy DCA for uplink communications may provide better overall performance in crowded short packet conditions, but may not match the performance achieved by using EDCA for both uplink and downlink communications in uncrowded short packet conditions.

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